Fluid mixing method and apparatus



Apnl 19, 1966 c. L. ASHBROOK FLUID MIXING METHOD AND APPARATUS 2 Sheets-Shet 1 Filed Jan. 2, 1963 p i 1966 c. L. ASHBROOK 3,246,883

FLUID MIXING METHOD AND APPARATUS Filed Jan. 2, 1963 2 Sheets-Sheet 2 .III. "'1

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United States Patent 3 246,883 FLUID MIXING ME THGD AND APPARATUS Clifford L. Ashbroolr, Houston, Tex., assignor to Ashbrook Corporation, Houston, Tex., a corporation of Texas Filed Jan. 2, 1963, Ser. No. 248,973 19 Claims. (Cl. 259-147) This application is a continuation-in-part of my application Serial No. 244,318 entitled Method of Mixing Fluids and Particulate Solids, filed December 13, 1962, now abandoned.

This invention relates to methods and apparatus for the continuous mixing and combining of fluids, including gases and flowable solids, from two or more input streams having differing pressures and flow rates as well as for measuring and controlling fluid flow in general and for stripping gases from liquids.

As an example of one use of the invention, it is especially adapted for the continuous mixing of a liquid, such as water, with a particulate flowable solid, such as cement. Heretofore, attempts have been made to mix continuously with water or other liquids, solids of a relatively slowly wettable nature, such as in the mixing of cement and water, for example. In this latter specific case, batch mixing has almost universally been used, as with the conventional cement truck, although it has long been realized that a continuous in-line mixer would have great advantages over batch mixers for many applications.

Accordingly, it is an object of the present invention to provide novel methods and apparatus uniquely capable of mixing in a continuous flow-through manner, fluids and flowable solids otherwise mixable only with considerable recirculation such as water and cement, for

example.

As another example of a use of the invention, it is especially adapted for providing a pressurized gas output by continuously combining a plurality of streams of gas having differing pressures and flow rates, yet without feedback between high and low pressure gas inputs which would cause reverse flow through the low pressure input. A typical situation in which the problem of combining such gas inputs arises is in the natural gas industry, wherein gas wells produce gas at differing pressures and flow rates. Heretofore, the output of wells which produced gas at lower pressure than that of the output gas transmission line from the gas field might be burned, because it was not economical to utilize conventional compressors to raise its pressure to that of the output gas transmission line. The methods and apparatus of the present invention, being mechanically simple, without moving parts, and free from the necessity of supplying external power except for the pressurized gas being combined therein, have sufficient excess pressure so that in combination with the low pressure gas the combination will have suflicient pressure to cause flow in the output transmission line.

As still another example of a use of the invention, it is especially adapted for stripping gas from liquid, as in deaerating water, for example, and this may be accomplished according to the invention without the use of conventional vacuum pumps or the like as has heretofore been necessary.

The methods of thepresent invention are based on the use of apparatus somewhat related to that apparatus dis closed in my Patent No. 2,957,495, of October 25, 1960, wherein is disclosed the mixing of fluids. The methods of the present invention differ from those disclosed in said patent in a number of respects.

c Ce Thus, as to one aspect of the present invention, they are directed to the mixing of a particulate solid and a fluid, usually a liquid, to form a substantially homogeneous mixture. More specifically, such a method comprises the major steps of maintaining an advancing hollow cylindrical body of fluid rotating rapidly about an. axis to produce a central vortex by continuously introducing a stream of fluid of said body tangentially thereof and by introducing a particulate solid to said vortex at the inlet end thereof into contact with the inner walls of said rotating hollow cylindrical body and advancing it therewith. Thereafter, the rotating body of fluid carrying the solid is sharply diverted in its direction of advance at a point spaced from the point of introduction of solid and fluid.

As to another aspect of the present invention, its methods are directed to the continuous combining of a plurality of streams of gas having differing pressures and flow rates. This is accomplished by maintaining, in case of more than two gas inputs, a series of successive advancing hollow cylindrical bodies of gases, each rotating rapidly about an axis to produce a series of successive central vortexes by continuously introducing pressurized streams of said gases'to said bodies tangentially thereof and successively introducing gas from a preceding body to the vortex of a succeeding body into contact with the rotating body of gas in said succeeding body and advancing it therewith. The energy, that is, the product of the mass and velocity, of the gas introduced into each said vortex is substantially less, say by a factor of at least about 2 to 1 and preferably about 4 or 5 to l, of that of the gas in the rotating body preferably surrounding said vortex.

It is a particular feature of the invention that the pressure may be sensed at a point within the vortex, that is adjacent its central axis, and that the so sensed pressure may be utilized in a variety of ways, such as to control a fluid input as by suitable valve means. The pressure so sensed may also be used as an indication of mass flow or specific gravity, for sensing or control purposes, of the fluid passing through the whirling body with or without the introduction of a solid or fluid into its vortex. If the specific gravity of the fluid being sensed is kept constant, then the mass flow will be indicated, and the converse also holds true. A gas entrained in a liquid passing through-the rotating body may be removed from the vortex, if nothing is being introduced therein, so that gas stripping of a liquid may be provided by methods according to the present invention.

The novel apparatus of the present invention includes means for establishing a series of successive rotating cylindrical bodies of fluid having means for successively introducing fluids from a preceding rotating body to the vortex of a succeeding body, as well as means for sens-.

made to the following detailed description of preferred embodiments thereof, together with the appended drawings wherein:

FIG. 1 is a cross sectional elevation of one form of preferred apparatus according to the present invention;

FIGS. 2 and 3 are cross sectional views of the apparatus of FIG. 1 taken respectively on the lines-22 and 3-3 thereof;

FIG. 4 is a cross sectional view of another form of preferred apparatus according to the present invention taken on the line d i of FIG. 5; and

FIG. 5 is a cross sectional view of FIG. 4 taken on the line 55 thereof.

Referring to the drawings, the device of the nvention especially useful for mixing a particulate solid and a liquid to form a substantially homogeneous mixture is shown in FIGS. l4. It comprises an inner tubular member 24 and a surrounding outer tubular member 30 mounted thereon at a position spaced from the outlet end of said inner tubular member by means of a body member 44 The inner tubular member 2% provides an elongated central chamber 22 having at its inlet end, within body member 40, an enlarged cylindrical port on 42 having a tangentially directed inlet opening 44 of pipe 46 for introducing a stream of liquid into said inner tubular member and creating a rapidly rotating whirling body of said liquid L with an axially extending central vortex V as said liquid passes through said central chamber 22. An inlet tube 50 having its axis directed along the axis of the inner tubular member 20 and of smaller diameter than said inner tubular member is provided extending in a straight line into said inner tubular member beyond cylindrical portion 42 for directing an axial stream of a particulate solid S into the vortex of the whirling body of liquid. The surrounding outer elongated tubular member 30 is spaced outwardly from inner tubular member 20 to provide an enclosed outer annular chamber 31 in communication with said inner tubular member. By reason of body member 40, outer tubular member 39 has an end wall 32 adjacent its mounting position and as well has an outlet opening at outlet pipe 34 adjacent said end wall 32. The outlet end 21 of said inner tubular member 2% terminates adjacent the opposite end wall 36, said end wall being closed off so that the mixture of said liquid and solid is forced to move radially outwardly from the end of said inner tubular member. A high fluid shear occurs at outlet end 21. This results in the central vortex V being destroyed and the completion of mixing of said mixture while the mixture moves in a helical path along the annular chamber 31 between said inner and outer tubular members to said outlet opening of said outer tubular member. Means are also provided for advancing a central portion 38 of end wall 36 toward and away from the open end of inner tube 20, said means consisting of a stud 37 thread-ed through end wall 36 for rotation by nut 39 thereon.

According to one aspect of the present invention, pressure sensing means are provided for controlling the introduction of particulate solid S through inlet tube 50. Such pressure sensing means senses the pressure of the vortex, and, to that end, is in the form of a pressure communicating tube 52 extending along the inner Wall of inlet tube 50 with its end opening 54 within the vortex V. The other end of pressure communicating tube 52 may be connected to an indicator 55 to measure or otherwise provide an indication of the pressure within the vortex. It may also be used to control one of the inputs to the device. For the latter purpose, valve means may be provided responsive to the pressure sensing means for controlling movement of one of said streams, for example either the axially directed stream of particulate solid passing through inlet tube 50 or the inlet of fluid through pipe 46. Such valve means for controlling the axially directed stream may bein the form of a slide valve 86 mounted in a suitable housing 82, the valve being actuated by a piston 84 operating within a cylinder 86 to which pressure communicating tube 52 is connected. A spring 88 is provided for normally maintaining slide valve 8%) in its closed position. Similar valve means including a slide valve 80a: mounted 4; in housing 8211 may be provided to control the inlet of fluid through pipe 46.

In operation of the above described device to mix cement and water, for example, with valve in its normally closed position, water, under pressure, say, of at least about 25 p.s.i., is introduced to pipe 46. By reason of the tangentially directed inlet 44, at the upper end of tube 20 a downwardly advancing hollow cylindrical body of water L is immediately created which rotates rapidly about a vertical axis to produce a central vortex V having a pressure much reduced from that of the inlet pressure of the water, and normally reduced with respect to atmospheric pressure. The latter reduced pressure, sensed at open end 54 of tube 52 is communicated to cylinder 86 which causes piston 84 to be moved in opposition to its spring 88, atmospheric pressure being applied on the other side of said piston, and open the valve 80 for introduction of the particulate solid cement S through tube 50. Thus, the cement S is introduced, at a rate controlled by the sensed value of the pressure within the vortex, to said vortex at the upper end thereof into contact with the inner walls of the rotating cylindrical body of water L and advances downwardly therewith. However, if the supply of water is cut off for any reason, the pressure at the end of tube 52 immediately rises and valve 80 is immediately closed by its spring 88 to cut oil? the introduction of cement S as well. When the rotating body of cement and water reaches portion 33 of end wall 36, it is sharply diverted radially as to its direction of advance at a point spaced below the point of introduction of the cement and at the end 21 of inner tube 2% for homogeneously mixing the cement and water as required. This is accomplished by the establishing by means of said end wall portion 38 of an upwardly advancing rotating body of water and cement in the annular volume 31 between the inner and outer tubular members and surrounding the downwardly advancing body, the homogeneous mixture being discharged through outlet pipe 34. End wall portion 38 makes possible the adjustment of the vortex pressure sensed by tube 52 and hence the control of valve 80.

FIGS. 4 and 5 of the drawings show a device of the invention particularly adapted for combining a plurality of streams of gases or other fluids having differing pressures and flow rates, yet without feedback between high and low pressure gas inputs which would cause reverse flow at the low pressure gas input.

As described above, it includes an inner tubular member 20' and a surrounding outer tubular member 30' mounted thereon at a position spaced from the outlet end of said inner tubular member by means of a body member 40. The inner tubular member 20' provides an elongated central chamber 2 2 having at its inlet end Within body member 40' an enlarged cylindrical portion 42' having a tangentially directed inlet opening 44' of pipe 4 6' for introducing a stream of liquid into said inner tubular member 20 and creating a rapidly rotating Whirlmg body of said liquid with an axially extending central vortex as said liquid passes through said central chamber 22. The surrounding outer elongated tubular member 30 is spaced outwardly (from inner tubular member 20' to provide an enclosed outer annular chamber 31 in com munication with said inner tubular member. By reason of body member 40', outer tubular member 30 has an end Wall 32 adjacent its mounting position and as well has an outlet opening at outlet pipe -34 adjacent said end wall 32'. The outlet end 21' of said inner tubular member 20' terminates adjacent the opposite end wall 36, said end wall being closed off so that the combined streams are forced to move radially outwardly from the end of said inner tubular member. This results in the central :vortex being destroyed with the combined streams moving in a helical path along the annular chamber 31 between said inner and outer tubular members to said outlet opening of said outer tubular member.

The device of FIGS. 4 and 5 differes trom that of FIGS. 1-3 in that additional body members 60 and 70 are utilized, together with vortex tubes 69, 79, respectively, extending downwardly therefrom into the succeeding chamber 62, 42, respectively, two being herein shown, although any desired number thereof may .be utilized. Such body members are generally similar, each having an enlarged cylindrical portion 62, 72 with a tangentially directed inlet opening 64, 74 for inlet pipes 66, 76 for introducing a stream of gas or other fluid into said portion 62, 72 and creating a rapidly rotating whirling body of gas which advances into the vortex of a succeeding rotating .body of gas through restricted portions 68, 78 and vortex tubes 69, 79 of said body portions which confine the rotating body of gas to the vortex of each succeeding body. An inlet tube 50' having its axis directed along the axes of the inner tubular member 20' and body members 40', 60, 70 and of smaller diameter than said inner tubular member and the restricted portions and vortex tube or": said body members may be provided extending in a straight line into said inner tubular member for directing an axial stream of a gas into the vortex of the whirling body of gases, or for measurement or control purposes as set torth herein.

In operation of the device of FIGS. 4 and 5 to combine streams of gases or other fluids at differing presssures and volumes, the inputs of gases should be arranged in order of successively increasing energy content, that is, with the highest energy gas being introduced at inlet pipe 46' and the lowest energy gas being introduced at inlet pipe 76, or at central inlet tube 50'. The energy of the gas introduced may be considered to be roughly proportional to the product of its mass, pressure and rate of flow, although With the same kind of gas introduced at each inlet the factors of pressure and rate of flow are sufficient. 'Ioo, the computation must be on the basis of the total gas at a given point within the device. Conventionally, since inlet pressures do not vary Widely, at least to the extent that inlet volume may when the outputs of a plurality of gas wells are to be combined, the connections may be in the order of increasing volumes, without regard .to pressures, since the rotating bodies of gas operate to prevent feedback from a high pressure to a low pressure source. The central inlet can be utilized as a means for sensing vortex pressures, for purposes of measurement or control of inlets, such as by suitable valves, as set forth above, as to shut off inlets in case of a sensed pressure use, for example.

As a typical illustration of the operation of such a device to combine streams of gas, gas at 190 p.s.i. and 15 cu. ft./min. was introduced at inlet 46, gas at 140 p.s.i. and cu. ft./min. was introduced at inlet 66, and gas at 90 psi. at 5 cu. ft./min. was introduced at inlet 76. The pressure drop within each stage was about 40 psi. and the exit pressure was 116.6 p.s.i.

This result is shown as follows.

At inlet 46: cu. ft./min. gas at 150 p.-s.i. =10.4\2 atmosphere pressure or 10.42 15=156.3 cu. it/min. of gas at 1 atmosphere pressure.

Art inlet 66: 10 cu. ft/min. gas at 100 p.s.si. =6.8 atmos. or 6.8 10=68 cu. ft/min. of gas at 1 atmos.

At inlet 76: 5 cu. ft./|min. gas at 50 p.s.i.=3.4 atmos. or 3.4 5= 17 cu. f-L/min. of gas at 1 atmos, a combined total of 241.3 cu. ft./rnin. of gas at 1 atmos. pressure.

Standardizing gas mass and adding:

15 cu. it./min.=50% or 3 units of pressure or 3 X 150=45O 10 cu. ft./1nin.= 3% or 2 units of pressure or 2 X 100:200 5 cu. ft./min.=17% or 1 unit of pressure or 1 X 50 50 m=l00% or 6 units of pressure or 7 0 0 700/6 116.16 average p.s.i.

Summarizing: Exit volume of gas is 241.3 cu. ft/min. +(116.6/14.7) or 7.92 atrnos.=241.3/7.92=30.14 cu. ft./min. at new pressure of 116.6 p.s.i.

It will be noted that on a volumetric basis, there is 1 part of the gas introduced at inlet pipe 76 to 4 parts of the gas introduced at inlet 66 and one part of the combined gases introduced at inlets 76 and 66 to 1.83 parts introduced at inlet pipe 46', and such ratio should preferably be at least as great as 4, but may (be as low as 2 to 1 under some circumstances.

Turning now to a more general discussion of the apparatus and methods of the invention in terms of the above described device, it will be apparent that many uses or the dWlC6, even those including the mixing of cement and water, will not require the use of control of an input by sensing the fluid vortex pressure and in such uses the appropriate elements therefor may 'be omitted.

The present invention further contemplates the use of the device as a flowmeter, specific gravity meter, or as a gas stripper.

For use as a flowmeter or specific gravity meter, the fluid, gas or liquid, to be measured is introduced to the device of FIGS. 1-3 through tangential inlet 44 and passes outwardly through outlet 34 in the manner above described. The inlet tube 56) is not used for the introduction of any fluid or particulate solid, but may be connected to indicator 55 or to a recording meter, if desired. It tube 50 is so used as a substitute for tube 52, the latter need not be used, of course. With fluid flowing through the device, the pressure at the vortex is proportional to the mass flow through the meter, so that indicator 55 or a recording meter, connected to tube 52 or 54, will indicate the quantity of fluid passing through the device, if the specific gravity or density of said fluid be uniform, and, if it not be uniform, will indicate the mass of fiuid passing therethrough. The latter occurs with mixtures of gases, for example, combustible gases used as fuel. The mass of gas may be similarly determined by tube 50 in the device of FIGS. 4 and 5. End wall portion 38 may be used to change the back pressure within the device for purposes of adjustment, and the device of FIGS. 4 and 5 may be similarly provided therewith if desired.

For use as a gas stripper, the liquid to be stripped of entrained gas is passed through tangential inlet 44 of the device of FIGS. 1-3 and is removed from outlet 34 in the manner described above. Central tube 50 is used as an outlet for the gases evolved into vortex V and the pressure sensed by tube 52 may be utilized to control valve if desired. In the gas stripping operation, however, it is preferable to adjust the back pressure by increasing it, this resulting in the evolution of gas at a higher pressure than atmospheric to avoid its having to be pumped from the vortex V. Such is most etfective in removing the entrained air from water, the back pressure on the liquid flowing from the end of inner tube 20 being increased by advancing end wall portion 38 toward the end of inner tube 20 until air flows outwardly from tube 55). This desired operation can be controlled so as to shut oflf the water inlet if positive pressure fails by operating valve 80 in pipe 46 and arranging it in the opposite sense from that shown herein to open when positive pressure is applied to it, as by connecting pipe 52 to the other side of piston 84 than that shown. The back pressure may be provided by other means as Well.

Thus, it will be seen that the invention provides novel means and methods for the continuous mixing and combining of fluids including gases and particulate flowable solids, from two or more input streams having differing pressures and flow rates as well as for sensing and measuring fluid flow and for stripping gases from liquids. Various modifications of the invention, not herein disclosed, will be apparent to those skilled in the art.

I claim:

1. The method of mixing a particulate solid and a fluid to form a substantially homogeneous mixture which comprises the steps of: maintaining a continuously advancing hollow cylindrical body of fluid rotating rapidly about an axis to produce a central vortex by continuously introducing a stream of fluid to said body tangentially thereof, introducing a particulate solid to said vortex at the inlet end thereof into contact with the inner walls of said rotating hollow cylindrical body of fluid and advancing it therewith, and homogeneously mixing said solid and fluid by sharply diverting the direction of advance of the entire mass of said rotating body of fluid and said particulate solid at a point spaced from the point of introduction of said particulate solid to said vortex by establishing an outer rotating body of said fluid and solid in a helical path and advancing it in the opposite direction from said inner advancing body.

2. The method as claimed in claim 1 wherein said solid includes cement and said liquid is water.

3. The method of mixing a particulate solid and a fluid to form a substantially homogeneous mixture which comprises the steps of: maintaining an advancing hollow cylindrical body of fluid rotating rapidly about a vertical axis to produce a central vortex having a reduced pressure by continuously introducing a stream of fluid to said body tangentially thereof, sensing the pressure at a point within said vortex and by introducing, at a rate controlled by the sensed value of said pressure, a particulate solid to said vortex at the inlet end thereof into contact with the inner walls of said rotating hollow cylindrical body of fluid and advancing it therewith.

4. The method of mixing a particulate solid and a liquid to form a substantially homogeneous mixture which comprises the steps of: maintaining an advancing hollow cylindrical body of fluid rotating rapidly about a vertical axis to produce a central vortex having a reduced pressure by continuously introducing a stream of fluid to said body tangentially thereof, sensing the pressure at a point within said vortex by introducing, at a rate con trolled by the sensed value of said pressure, a particulate solid to said vortex at the inlet end thereof into contact with the inner walls of said rotating hollow cylindrical body of fluid and advancing it therewith, and homogeneously mixing said solid and fluid by sharply diverting the direction of advance of said rotating body of fluid and said particulate solid at a point spaced from the point of introduction of said particulate solid to said vortex.

5. The method of mixing a particulate solid and a fluid to form a substantially homogeneous mixture which comprises the steps of: maintaining an advancing hollow cylindrical body of fluid rotating rapidly about a vertical axis to produce a central vortex by continuously introducing a stream of fluid to said body tangentially thereof at the inlet end thereof, by introducing a particulate solid to said vortex at the inlet end thereof into contact with the inner walls of said rotating hollow cylindrical body of fluid and advancing it therewith and homogeneously mixing said solid and fluid by sharply diverting the direction of advance of said rotating body of fluid and said particulate solid at a point spaced from the point of introduction of said particulate solid to said vortex by establishing an outer rotating body of said fluid and solid surrounding said inner advancing body and advancing in the opposite direction therefrom.

6. The method of mixing particulate solid cement and water to form a substantially homogeneous mixture which comprises the steps of: maintaining a downwardly advancing hollow cylindrical body of water rotating rapidly about a vertical axis to produce a central vortex having a reduced pressure by continuously introducing a pressurized stream of water to said body tangentially thereof at the upper end thereof, sensing the pressure at a point within said vortex by introducing, at a rate controlled by the sensed value of said pressure, particulate solid cement to said vortex at the upper end thereof into contact with the inner walls of said rotating hollow cylindrical body of water and advancing it downwardly therewith and homogeneously mixing said water and solid cement by sharply diverting the direction of advance of said rotating body of water and said particulate solid cement at a point spaced below the point of introduction of said particulate solid cement to said vortex by establishing an upwardly advancing rotating body of said water and solid cement surrounding said downwardly advancing body thereof.

7. The method of sensing fluid flow comprising the steps of: maintaining an advancing hollow cylindrical body of fluid rotating rapidly about a central axis to produce a central vortex by continuously introducing a stream of fluid to said body tangentially thereof and sensing the pressure at a point within said vortex adjacent its central axis.

8. The method of sensing fluid flow comprising the steps of: maintaining an advancing hollow cylindrical body of fluid rotating rapidly about a central axis to produce a central vortex by continuously introducing a stream of fluid to said body tangentially thereof, sensing the pressure at a point within said vortex adjacent its central axis, and sharply diverting the direction of advance of the entire mass of said rotating body of fluid at a point spaced from the point at which said pressure is sensed.

9. The method of providing a pressurized fluid output by continuously combining a plurality of streams of fluid having differing pressures and flow rates without feedback between high and low pressure fluid inputs which comprises the steps of: maintaining a series of successive advancing hollow cylindrical bodies of fluids each rotating rapidly about an axis to produce a series of successive central vortexes by continuously introducing pressurized streams of said fluids to said bodies tangentially thereof and successively introducing fluid (from a preceding body to the vortex of a succeeding body into contact with the rotating body of fluid of said succeeding body and advancing it therewith, the energy of fluid introduced into each said vortex being substantially less than in said rotating body of fluid, and the entire mass of the last succeeding body of fluid being sharply diverted in its direction of advance.

10. The method of providing a pressurized gas output by continuously combining a plurality of streams of gas having differing pressures and flow rates without feedback between high and low pressure gas inputs causing reverse flow at the low pressure gas input which comprises the steps of: maintaining a series of successive advancing hollow cylindrical bodies of gases each rotating rapidly about an axis to produce a series of successive central vortexes by continuously introducing pressurized streams of said gases to said bodies tangentially thereof and successively introducing gas from a preceding body to the vortex of a succeeding body into contact with the rotat ing body of gas of said succeeding body and advancing it therewith, the energy of the gas introduced into each said vortex of a body of gas being substantially less by a factor of at least about 4-5 to 1 of the energy of the gas in said body.

1-1. A device for combining a plurality of streams of fluids comprising an inner tubular member and a surrounding outer tubular member, said inner tubular member providing an elongated central chamber having at its inlet end a plurality of axially spaced tangentially directed inlet openings having reduced portions there between for introducing streams of fluid into said tubular member and creating a series of rapidly rotating whirling bodies of said fluids with axially extending central vortexes as said fluids pass through said central chamber, said surrounding outer elongated tubular member being spaced outwardly from said inner tubular member to provide an enclosed annular chamber in communication with said inner tubular member, said outer tubular member further having an end wall adjacent the inlet end of said inner tubular member and having an outlet opening adjacent said end wall thereof, the outlet end of said inner tubular member terminating adjacent the opposite end wall of said outer tubular member, said opposite end wall of the outer tubular member being closed off so that said fluids move radially outwardly from the end of said inner tubular member and said central vortex is destroyed and the mixing of said fluids is completed while said fluids move in a helical path along the annular chamber between said inner and Outer tubular members to said outlet opening of said outer tubular member.

12. A device for continuously providing a pressurized fluid output from the inputs of a plurality of streams of fluid having differing pressures and flow rates without feedback between high and low pressure fluid inputs causing reverse flow at the low pressure fluid input which comprises means for maintaining a series of successive advancing hollow cylindrical bodies of fluid each rotating rapidly about an axis to producea series of successive central vortexes by continuously introducing pressurized streams of said fluids to said bodies tangentially thereof, means for successively introducing fluid from a preceding body to the vortex of a succeeding body into contact with the rotating body of fluid of said succeeding body and advancing it therewith and means for sharply diverting the direction of advance of said rotating body of fluid.

13. A device for mixing a particulate solid and a liquid to form a substantially homogeneous mixture, said device comprising an inner tubular member and a surrounding outer tubular member mounted thereon at a position spaced from the outlet end of said inner tubular member, said inner tubular member providing an elongated central chamber having at its inlet end a tangentially directed inlet opening for introducing a stream of liquid into said inner tubular member and creating a rapidly rotating whirling body of said liquid with an axially extending central vortex as said liquid passes through said central chamber, pressure sensing means for sensing the pressure at a point within said vortex, an inlet opening having its axis directed along the axis of said inner tubular member for directing an axial stream of a particulate solid into the vortex of the whirling body of said liquid, valve means responsive to said pressure sensing means for controlling movement of said axially directed stream of particulate solid in a straight downward path through said axially directed inlet from said valve means, said surrounding outer elongated tubular member being spaced outwardly from said inner tubular member to provide an enclosed annular chamber in communication with said inner tubular member, said outer tubular member further having an end wall adjacent said mounting position and having an outlet opening adjacent said end wall thereof, the outlet end of said inner tubular member terminating adjacent the opposite end wall of said outer tubular member, said opposite end Wall of the outer tubular member being closed off so that the mixture of said liquid :and solid moves radially outwardly from the end of said inner tubular member and said central vortex is destroyed and the mixing of said mixture is completed while said mixture moves in a helical path along the annular chamber between said inner and outer tubular members to said outlet opening of said outer tubular member.

14. A device for mixing a particulate solid and a fluid comprising an inner tubular member and a surrounding outer tubular member, said inner tubular member providing an elongated central chamber having at its inlet end a tangentially directed inlet opening for introducing a stream of fluid into said tubular member and creating a rapidly rotating whirling body of said fluid with an axially extending central vortex as said fluid passes through said central chamber, pressure sensing means for sensing the pressure at a point within said vortex, an inlet opening having its axis directed along said inner tubular member for directing an axial stream of a particulate solid into the vortex of the whirling body of said fluid, and valve means responsive to said pressure sensing means for controlling movement of one of said streams, said surrounding outer elongated tubular member being spaced outwardly from said inner tubular member to provide an 10 enclosed annular chamber in communication with said inner tubular member, said outer tubular member further having an end wall adjacent the inlet end of said inner tubular member and having an outlet opening adjacent said end wall thereof, the outlet end of said inner tubular member terminating adjacent the opposite end wall of said outer tubular member, said opposite end wall of the outer tubular member being closed elf so that said fluids I'nove radially outwardly from the end of said inner tubular member and said central vortex is destroyed and the mixing of said fluids is completed while said fluids move in a helical path along the annular chamber between said inner and outer tubular members to said outlet opening of said outer tubular member.

15. A device for mixing a particulate solid and a fluid comprising a tubular member providing an elongated central chamber having at its inlet end a tangentially directed inlet opening for introducing a stream of fluid into said tubular member and creating a rapidly rotating whirling body of said fluid with an axially extending central vortex as said fluid passes through said central chamber, pressure sensing means for sensing the pressure at a point within said vortex, an axially directed inlet opening having its axis directed along said tubular member for directing an axial stream of a particulate solid into the vortex of the whirling body of said fluid, valve means responsive to said pressure sensing means for controlling movement of one of said streams and an end wall spaced from the end of said tubular member so that said fluids move radially outwardly from the end of said tubular member and said central vortex is destroyed and the mixing of said fluids is completed.

16. A device for mixing a particulate solid and a fluid comprising a tubular member providing an elongated central chamber having at its inlet end a tangentially directed inlet opening for introducing a stream of fluid into said tubular member and creating a rapidly rotating whirling body of said fluid with an axially extending central vortex as said fluid passes through said central chamber, pressure sensing means for sensing the pressure at a point within said vortex, an axially directed inlet opening having its axis directed along said tubular member for directing an axial stream of a particulate solid into the vortex of the whirling body of said fluid, and valve means responsive to said pressure sensing means for controlling movement of one of said streams.

17. A device for controlling fluid flow comprising a tubular member providing an elongated central chamber having at its inlet end a tangentially directed inlet opening for introducing a stream of fluid into said tubular member and creating a rapidly rotating whirling body of said fluid with an axially extending central vortex as said fluid passes through said central chamber, pressure sensing means for sensing the pressure at a point within said vortex, valve means responsive to said pressure sensing means for controlling movement of said stream, and an end wall spaced from the end of said tubular member so that said fluid moves radially outwardly from the end of said tubular member and said central vortex is destroyed.

18. A device for controlling fluid flow comprising a tubular member providing an elongated central chamber having at its inlet end a tangentially directed inlet open- 111g for introducing a stream of fluid into said tubular member and creating a rapidly rotating whirling body of said fluid with an axially extending central vortex as said fluid passes through said central chamber, pressure sensing means for sensing the pressure at a point Within said vortex, and valve means responsive to said pressure sensing means for controlling movement of said stream.

19. A device for sensing fluid flow comprising a tubular member providing an elongated central chamber having at its inlet end a tangentially directed inlet opening for introducing a stream of fluid into said tubular member and creating a rapidly rotating whirling body of said fluid with an axially extending central vortex as said fluid means for sensing the pressure at a point within said vortex.

References Cited by the Examiner UNITED STATES PATENTS 928,546 7/1909 Schneible 55184 2,721,147 10/1955 Sullivan 259147 X 2,724,580 11/ 1955 Revallier 2594 FOREIGN PATENTS I 815,247" 4/1937 France. 1,094,231 12/1954 France.

CHARLES A. WILLMUTH, Examiner. 

1. THE METHOD OF MIXING A PARTICULATE SOLID AND A FLUID TO FORM A SUBSTANTIALLY HOMOGENEOUS MIXTURE WHICH COMPRISES THE STEPS OF: MAINTAINING A CONTINUOUSLY ADVANCING HOLLOW CYLINDRICAL BODY OF FLUID ROTATING RAPIDLY ABOUT AN AXIS TO PRODUCE A CENTRAL VORTEX BY CONTINUOUSLY INTRODUCING A STREAM OF FLUID TO SAID BODY TANGENTIALLY THEREOF, INTRODUCING A PARTICULATE SOLID TO SAID VORTEX AT THE INLET END THEREOF INTO CONTACT WITH THE INNER WALLS OF SAID ROTATING HOLLOW CYLINDRICAL BODY OF FLUID AND ADVANCING IT THEREWITH, AND HOMOGENEOUSLY MIXING SAID SOLID AND FLUID BY SHARPLY DIVERTING THE DIRECTION OF ADVANCE OF THE ENTIRE MASS OF SAID ROTATING BODY OF FLUID AND SAID PARTICULATE SOLID AT A POINT SPACED FROM THE POINT OF INTRODUCTION OF SAID PARTICULATE SOLID TO SAID VORTEX BY ESTABLISHING AN OUTER ROTATING BODY OF SAID FLUID AND SOLID IN A HELICAL PATH AND ADVANCING IT IN THE OPPOSITE DIRECTION FROM SAID INNER ADVANCING BODY. 